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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Mudança dos valores pessoais ao longo do ciclo de vida das pessoas

Duschitz, Caroline da Costa January 2013 (has links)
Esta pesquisa, com caráter conclusivo descritivo, buscou verificar se os valores pessoais mudam ao longo da vida, comparando-se dois diferentes momentos – em torno dos 25 anos e em torno dos 60 anos. Tendo como principal referencial teórico os trabalhos de Schwartz (1992; 2005b) e de Bardi et al. (2009), questionaram-se 106 pessoas que vivem, predominantemente, na região metropolitana de Porto Alegre, através de survey (PVQ-21) aplicada em entrevistas face a face, sobre os valores pessoais hoje e, com perguntas com abordagem histórico-longitudinal, resgataram-se os valores pessoais em torno dos 25 anos. O comparativo intragrupo foge das abordagens que contrastam valores pessoais entre gerações diferentes. Nesta amostra, observou-se a constância dos valores “Hedonismo” e “Conformidade” – diferentemente da teoria que previa que o primeiro teria menor importância com o avançar da vida e que o segundo tornar-se-ia mais importante; portanto, observa-se a busca pelo prazer como constante na vida das pessoas e que, ao longo da vida, as pessoas permanecem respeitando as diferenças de status e as expectativas sociais. Replicando-se achados de outros autores, verificou-se também a grande similaridade e mistura entre os valores “Realização” e “Poder”. Além disso, os valores de “Autotranscendência” e “Abertura à Mudança” estiveram muito próximos nos dois períodos contrastados – o que pode indicar que fazer o bem para os outros pode dar prazer e ser estimulante. Por fim, constatou-se que o nível de escolaridade é uma circunstância que impacta em muitas mudanças de valores e que a mudança do valor “Segurança” foi a mais correlacionada a eventos da vida. / This conclusive descriptive research aimed to verify whether the personal values change throughout life, comparing two different times - around 25 years and about 60 years. With the main theoretical work of Schwartz (1992, 2005b) and Bardi et al. (2009), 106 people that mostly live in Metropolitan Region of Porto Alegre were questioned, through survey (PVQ-21) applied in face to face interviews, about their personal values today and, with questions with longitudinal-historical approach, were rescued personal values when interviewed were around 25 years. The intra-group comparison differs from approaches that contrast personal values between different generations. In this sample, we observed the constancy of values "Hedonism" and "Conformity" – unlike the theory have predicted that the first would reduce importance with advancing life and the second would become more important; hence, the pursuit of pleasure was understood as a constant in people's lives and that throughout life, people remain respecting the differences of status and social expectations. Replicating the findings of other authors, it was also find the great similarity and mixing between the "Achievement" and "Power". Moreover, the values of "Self-Transcendence" and "Openness to Change" were very close in the two contrasted periods - which may indicate that doing good for others can be stimulating and pleasuring. Finally, it was found that the level of education is a condition that impacts many changes in values and change the value "Security" was the most correlated with life events.
62

Mudança dos valores pessoais ao longo do ciclo de vida das pessoas

Duschitz, Caroline da Costa January 2013 (has links)
Esta pesquisa, com caráter conclusivo descritivo, buscou verificar se os valores pessoais mudam ao longo da vida, comparando-se dois diferentes momentos – em torno dos 25 anos e em torno dos 60 anos. Tendo como principal referencial teórico os trabalhos de Schwartz (1992; 2005b) e de Bardi et al. (2009), questionaram-se 106 pessoas que vivem, predominantemente, na região metropolitana de Porto Alegre, através de survey (PVQ-21) aplicada em entrevistas face a face, sobre os valores pessoais hoje e, com perguntas com abordagem histórico-longitudinal, resgataram-se os valores pessoais em torno dos 25 anos. O comparativo intragrupo foge das abordagens que contrastam valores pessoais entre gerações diferentes. Nesta amostra, observou-se a constância dos valores “Hedonismo” e “Conformidade” – diferentemente da teoria que previa que o primeiro teria menor importância com o avançar da vida e que o segundo tornar-se-ia mais importante; portanto, observa-se a busca pelo prazer como constante na vida das pessoas e que, ao longo da vida, as pessoas permanecem respeitando as diferenças de status e as expectativas sociais. Replicando-se achados de outros autores, verificou-se também a grande similaridade e mistura entre os valores “Realização” e “Poder”. Além disso, os valores de “Autotranscendência” e “Abertura à Mudança” estiveram muito próximos nos dois períodos contrastados – o que pode indicar que fazer o bem para os outros pode dar prazer e ser estimulante. Por fim, constatou-se que o nível de escolaridade é uma circunstância que impacta em muitas mudanças de valores e que a mudança do valor “Segurança” foi a mais correlacionada a eventos da vida. / This conclusive descriptive research aimed to verify whether the personal values change throughout life, comparing two different times - around 25 years and about 60 years. With the main theoretical work of Schwartz (1992, 2005b) and Bardi et al. (2009), 106 people that mostly live in Metropolitan Region of Porto Alegre were questioned, through survey (PVQ-21) applied in face to face interviews, about their personal values today and, with questions with longitudinal-historical approach, were rescued personal values when interviewed were around 25 years. The intra-group comparison differs from approaches that contrast personal values between different generations. In this sample, we observed the constancy of values "Hedonism" and "Conformity" – unlike the theory have predicted that the first would reduce importance with advancing life and the second would become more important; hence, the pursuit of pleasure was understood as a constant in people's lives and that throughout life, people remain respecting the differences of status and social expectations. Replicating the findings of other authors, it was also find the great similarity and mixing between the "Achievement" and "Power". Moreover, the values of "Self-Transcendence" and "Openness to Change" were very close in the two contrasted periods - which may indicate that doing good for others can be stimulating and pleasuring. Finally, it was found that the level of education is a condition that impacts many changes in values and change the value "Security" was the most correlated with life events.
63

Natural Correlations of Spectral Envelope and their Contribution to Auditory Scene Analysis

January 2017 (has links)
abstract: Auditory scene analysis (ASA) is the process through which listeners parse and organize their acoustic environment into relevant auditory objects. ASA functions by exploiting natural regularities in the structure of auditory information. The current study investigates spectral envelope and its contribution to the perception of changes in pitch and loudness. Experiment 1 constructs a perceptual continuum of twelve f0- and intensity-matched vowel phonemes (i.e. a pure timbre manipulation) and reveals spectral envelope as a primary organizational dimension. The extremes of this dimension are i (as in “bee”) and Ʌ (“bun”). Experiment 2 measures the strength of the relationship between produced f0 and the previously observed phonetic-pitch continuum at three different levels of phonemic constraint. Scat performances and, to a lesser extent, recorded interviews were found to exhibit changes in accordance with the natural regularity; specifically, f0 changes were correlated with the phoneme pitch-height continuum. The more constrained case of lyrical singing did not exhibit the natural regularity. Experiment 3 investigates participant ratings of pitch and loudness as stimuli vary in f0, intensity, and the phonetic-pitch continuum. Psychophysical functions derived from the results reveal that moving from i to Ʌ is equivalent to a .38 semitone decrease in f0 and a .75 dB decrease in intensity. Experiment 4 examines the potentially functional aspect of the pitch, loudness, and spectral envelope relationship. Detection thresholds of stimuli in which all three dimensions change congruently (f0 increase, intensity increase, Ʌ to i) or incongruently (no f0 change, intensity increase, i to Ʌ) are compared using an objective version of the method of limits. Congruent changes did not provide a detection benefit over incongruent changes; however, when the contribution of phoneme change was removed, congruent changes did offer a slight detection benefit, as in previous research. While this relationship does not offer a detection benefit at threshold, there is a natural regularity for humans to produce phonemes at higher f0s according to their relative position on the pitch height continuum. Likewise, humans have a bias to detect pitch and loudness changes in phoneme sweeps in accordance with the natural regularity. / Dissertation/Thesis / Doctoral Dissertation Psychology 2017
64

Mudança dos valores pessoais ao longo do ciclo de vida das pessoas

Duschitz, Caroline da Costa January 2013 (has links)
Esta pesquisa, com caráter conclusivo descritivo, buscou verificar se os valores pessoais mudam ao longo da vida, comparando-se dois diferentes momentos – em torno dos 25 anos e em torno dos 60 anos. Tendo como principal referencial teórico os trabalhos de Schwartz (1992; 2005b) e de Bardi et al. (2009), questionaram-se 106 pessoas que vivem, predominantemente, na região metropolitana de Porto Alegre, através de survey (PVQ-21) aplicada em entrevistas face a face, sobre os valores pessoais hoje e, com perguntas com abordagem histórico-longitudinal, resgataram-se os valores pessoais em torno dos 25 anos. O comparativo intragrupo foge das abordagens que contrastam valores pessoais entre gerações diferentes. Nesta amostra, observou-se a constância dos valores “Hedonismo” e “Conformidade” – diferentemente da teoria que previa que o primeiro teria menor importância com o avançar da vida e que o segundo tornar-se-ia mais importante; portanto, observa-se a busca pelo prazer como constante na vida das pessoas e que, ao longo da vida, as pessoas permanecem respeitando as diferenças de status e as expectativas sociais. Replicando-se achados de outros autores, verificou-se também a grande similaridade e mistura entre os valores “Realização” e “Poder”. Além disso, os valores de “Autotranscendência” e “Abertura à Mudança” estiveram muito próximos nos dois períodos contrastados – o que pode indicar que fazer o bem para os outros pode dar prazer e ser estimulante. Por fim, constatou-se que o nível de escolaridade é uma circunstância que impacta em muitas mudanças de valores e que a mudança do valor “Segurança” foi a mais correlacionada a eventos da vida. / This conclusive descriptive research aimed to verify whether the personal values change throughout life, comparing two different times - around 25 years and about 60 years. With the main theoretical work of Schwartz (1992, 2005b) and Bardi et al. (2009), 106 people that mostly live in Metropolitan Region of Porto Alegre were questioned, through survey (PVQ-21) applied in face to face interviews, about their personal values today and, with questions with longitudinal-historical approach, were rescued personal values when interviewed were around 25 years. The intra-group comparison differs from approaches that contrast personal values between different generations. In this sample, we observed the constancy of values "Hedonism" and "Conformity" – unlike the theory have predicted that the first would reduce importance with advancing life and the second would become more important; hence, the pursuit of pleasure was understood as a constant in people's lives and that throughout life, people remain respecting the differences of status and social expectations. Replicating the findings of other authors, it was also find the great similarity and mixing between the "Achievement" and "Power". Moreover, the values of "Self-Transcendence" and "Openness to Change" were very close in the two contrasted periods - which may indicate that doing good for others can be stimulating and pleasuring. Finally, it was found that the level of education is a condition that impacts many changes in values and change the value "Security" was the most correlated with life events.
65

Recreating a functioning forest soil in reclaimed oil sands in northern Alberta

Rowland, Sara Michelle 05 1900 (has links)
During oil-sands mining all vegetation cover, soil, overburden and oil-sand is removed, leaving pits several kilometres wide and hundreds of metres deep. These pits are reclaimed by a variety of treatments using mineral soil or a mixed peat and mineral soil as the capping layer and planted with trees with natural colonisation from adjacent sites. A number of reclamation treatments covering different age classes were compared with a range of natural forest ecotypes to identify the age at which the treatments become similar to a natural site with respect to vegetation composition and key soil attributes relevant to nutrient cycling. Ecosystem function was estimated from plant community composition, litter decomposition, development of an organic layer and bio-available nutrients. Key response variables including moisture, pH, C:N ratios, bio-available nutrients and ground-cover were analysed by non-metric multidimensional scaling and cluster analysis to discover which reclamation treatments were moving towards or merging with natural forest ecotypes and at what age this occurs. On reclaimed sites, bio-available nutrients including nitrate generally were above the natural range of variability but ammonium, phosphorus, potassium, sodium and manganese were generally very low and limiting to ecosystem development. Plant diversity was similar to natural sites from 5 years to 30 years after reclamation, but declined as reclaimed sites approached canopy closure. Grass and forb leaf litters decomposed faster than aspen or pine in the first year, but decomposition on one reclamation treatment fell below the natural range of variability. Development of an organic layer appeared to be facilitated by the presence of shrubs, while forbs correlated negatively with first-year decomposition of aspen litter. The better restoration amendments for tailings sands involved repeated fertilisation of peat: mineral mixtures in the early years of plant establishment, these became similar to a target ecotype at about 25 years. Good results were also shown by subsoil laid over non-saline overburden and fertilised once, these became similar to a target ecotype at about 15 years. Other treatments receiving a single application of fertiliser remain entrenched in the early reclamation phase for up to 25 years. / Forestry, Faculty of / Graduate
66

Finding groups of the similar variables with statistical software SAS and SPSS / Zjišťování skupin podobných proměnných v systémech SAS a SPSS

Marková, Monika January 2007 (has links)
My diploma thesis focuses on the comparison of possibilities of the statistical software SAS and SPSS in the area of the factor and cluster analysis and the multidimensional scaling. They deal with the methods for identifying groups of the similar statistical values (variables). The ascertained relations among the variables can serve to decrease the proportion vectors of the variables, which describe the individual monitored objects (statistical units), which helps us to apply other various methods, for example the regression or discriminant analysis. By one of the ways for finding the similarity of variables in the cluster analysis or the multidimensional scaling is searching for their relations. Whereas the base of the factor analysis is the formulation of the relation between two variables by means of the covariances, eventually Pearson correlation coefficient, it is possible to use also coefficients of correlation for the cluster analysis and the multidimensional scaling, in some case other measures. The thesis describes mainly the command syntax of the procedures implemented in SAS and SPSS. The meaning of the individual parametres and the partial specifications of each command are explained. The results gained by various types of analyses are compared on the basis of the real dataset. The possibilities of the statistical software SAS and SPSS are evaluated in the conclusion and it is referred to their advantages or disadvantages. The attention is also paid, for example, to the form of the input dataset, to the quaility of outputs or to the partial methods.
67

Geometria de distâncias euclidianas e aplicações / Euclidean distance geometry and applications

Lima, Jorge Ferreira Alencar, 1986- 26 August 2018 (has links)
Orientadores: Carlile Campos Lavor, Tibérius de Oliveira e Bonates / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Matemática Estatística e Computação Científica / Made available in DSpace on 2018-08-26T15:11:50Z (GMT). No. of bitstreams: 1 Lima_JorgeFerreiraAlencar_D.pdf: 1109545 bytes, checksum: 086223c23c920a9abe0d3661769a6a7d (MD5) Previous issue date: 2015 / Resumo: Geometria de Distâncias Euclidianas (GDE) é o estudo da geometria euclidiana baseado no conceito de distância. É uma teoria útil em diversas aplicações, onde os dados consistem em um conjunto de distâncias e as possíveis soluções são pontos em algum espaço euclidiano que realizam as distâncias dadas. O problema chave em GDE é conhecido como Problema de Geometria de Distâncias (PGD), em que é dado um inteiro K>0 e um grafo simples, não direcionado, ponderado G=(V,E,d), cujas arestas são ponderadas por uma função não negativa d, e queremos determinar se existe uma função (realização) que leva os vértices de V em coordenadas no espaço euclidiano K-dimensional, satisfazendo todas as restrições de distâncias dadas por d. Consideramos tanto problemas teóricos quanto aplicações da GDE. Em termos teóricos, demonstramos a quantidade exata de soluções de uma classe de PGDs muito importante para problemas de conformação molecular e, além disso, conseguimos condições necessárias e suficientes para determinar quando um grafo completo associado a um PGD é realizável e qual o espaço euclidiano com dimensão mínima para tal realização. Em termos práticos, desenvolvemos um algoritmo que calcula tal realização em dimensão mínima com resultados superiores a um algoritmo clássico da literatura. Finalmente, mostramos uma aplicação direta do PGD em problemas de escalonamento multidimensional / Abstract: Euclidean distance geometry (EDG) is the study of Euclidean geometry based on the concept of distance. This is useful in several applications, where the input data consists of an incomplete set of distances and the output is a set of points in some Euclidean space realizing the given distances. The key problem in EDG is known as the Distance Geometry Problem (DGP), where an integer K>0 is given, as well as a simple undirected weighted graph G=(V,E,d), whose edges are weighted by a non-negative function d. The problem consists in determining whether or not there is a (realization) function that associates the vertices of V with coordinates of the K-dimensional Euclidean space, in such a way that those coordinates satisfy all distances given by d. We considered both theoretical issues and applications of EDG. In theoretical terms, we proved the exact number of solutions of a subclass of DGP that is very important in the molecular conformation problems. Moreover, we described necessary and sufficient conditions for determining whether a complete graph associated to a DGP is realizable and the minimum dimension of such realization. In practical terms, we developed an algorithm that computes such realization, which outperforms a classical algorithm from the literature. Finally, we showed a direct application of DGP to multidimensional scaling / Doutorado / Matematica Aplicada / Doutor em Matemática Aplicada
68

Vowel perception in severe noise

Swanepoel, Rikus 05 March 2013 (has links)
A model that can accurately predict speech recognition for cochlear implant (CI) listeners is essential for the optimal fitting of cochlear implants. By implementing a CI acoustic model that mimics CI speech processing, the challenge of predicting speech perception in cochlear implants can be simplified. As a first step in predicting the recognition of speech processed through an acoustic model, vowel perception in severe speech-shaped noise was investigated in the current study. The aim was to determine the acoustic cues that listeners use to recognize vowels in severe noise and make suggestions regarding a vowel perception predictor. It is known that formants play an important role in quiet, while in severe noise the role of formants is still unknown. The relative importance of F1 and F2 is also of interest, since the masking of noise is not always evenly distributed over the vowel spectrum. The problem was addressed by synthesizing vowels consisting of either detailed spectral shape or formant information. F1 and F2 were also suppressed to examine the effect in severe noise. The synthetic stimuli were presented to listeners in quiet and signal-to-noise ratios of 0 dB, -5 dB and -10 dB. Results showed that in severe noise, vowels synthesized according to the whole-spectrum were recognized significantly better than vowels containing only formants. Multidimensional scaling and FITA analysis indicated that formants were still perceived and extracted by the human auditory system in severe noise, especially when the vowel spectrum consisted of the whole spectral shape. Although F1 and F2 vary in importance in listening conditions of quiet and less noisy conditions, the role of the two cues appears to be similar in severe noise. It was suggested that not only the availability formants, but also details of the vowel spectral shape can help to predict vowel recognition in severe noise to a certain degree. / Dissertation (MEng)--University of Pretoria, 2010. / Electrical, Electronic and Computer Engineering / unrestricted
69

PORTABLE INDOOR MULTI-USER POSITION TRACKING SYSTEM FOR IMMERSIVE VIRTUAL ENVIRONMENTS USING SENSOR FUSION WITH MULTIDIMENSIONAL SCALING

Vincent, David E. 01 May 2012 (has links)
No description available.
70

Selecting stimuli parameters for video quality studies based on perceptual similarity distances

Kumcu, A., Platisa, L., Chen, H., Gislason-Lee, Amber J., Davies, A.G., Schelkens, P., Taeymans, Y., Philips, W. 16 March 2015 (has links)
Yes / This work presents a methodology to optimize the selection of multiple parameter levels of an image acquisition, degradation, or post-processing process applied to stimuli intended to be used in a subjective image or video quality assessment (QA) study. It is known that processing parameters (e.g. compression bit-rate) or techni- cal quality measures (e.g. peak signal-to-noise ratio, PSNR) are often non-linearly related to human quality judgment, and the model of either relationship may not be known in advance. Using these approaches to select parameter levels may lead to an inaccurate estimate of the relationship between the parameter and subjective quality judgments – the system’s quality model. To overcome this, we propose a method for modeling the rela- tionship between parameter levels and perceived quality distances using a paired comparison parameter selection procedure in which subjects judge the perceived similarity in quality. Our goal is to enable the selection of evenly sampled parameter levels within the considered quality range for use in a subjective QA study. This approach is tested on two applications: (1) selection of compression levels for laparoscopic surgery video QA study, and (2) selection of dose levels for an interventional X-ray QA study. Subjective scores, obtained from the follow-up single stimulus QA experiments conducted with expert subjects who evaluated the selected bit-rates and dose levels, were roughly equidistant in the perceptual quality space - as intended. These results suggest that a similarity judgment task can help select parameter values corresponding to desired subjective quality levels. / Parts of this work were performed within the Telesurgery project (co-funded by iMinds, a digital research institute founded by the Flemish Government; project partners are Unilabs Teleradiology, SDNsquare and Barco, with project support from IWT) and the PANORAMA project (co-funded by grants from Belgium, Italy, France, the Netherlands, the United Kingdom, and the ENIAC Joint Undertaking).

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